Floating calipers, or “sliding” disc brake calipers in other words, having moveable caliper bodies on guides fixed to support brackets are known. In these known calipers, the braking action is exerted by thrust means, cylinder-piston means, positioned only on one side of the caliper body, the inner side or side facing towards the vehicle, to exert a thrust on friction elements, typically brake pads against a first braking surface which faces the inner side of the brake body.
For example, international patent application WO2012/156849 by the same applicant, shows calipers of the floating type for brake disc, in which, in order to reduce dimensions and weight, the supporting bracket is provided on only one side of the caliper, particularly on the inner side, and the sliding of the brake body with respect to the bracket, i.e. in axial direction, occurs on guiding pins.
However, because of their lightness and dimensions, the known calipers of floating type described here are subject to considerable deformation when subject to the braking action.
In particular, as known from patent FR1360566, the imbalance of the axial and tangential forces acting on the caliper body of the floating type tends to move the barycenter of the pressure areas on an associable brake disc, generating a self-locking effect of the caliper, and consequently localizing maximum wear on the side edges of the pads in contact with an associable brake disc.
The need is thus felt to compensate the imbalance of the braking action defined by the deformation of the caliper body and accentuated by the fact that the aforesaid guiding pins impose even minimum clearances in the sliding of the caliper body with respect to the bracket.
For example, from documents US2007/0256900A1, EP0145593B1, EP0489452A1 and JPH0932870A floating type calipers are known in which the pads or braking elements arranged on opposite sides of the brake caliper and facing towards opposite surfaces of an associable brake disc are arranged in misaligned position, i.e. in shifted position with respect to one another according to the circumferential coordinate of an associable brake disc, and particularly the inner braking element is arranged in advance relative to the sense of rotation of an associable brake disc. In these known solutions, a moment it thus generated on the caliper body which tends to compensate the imbalance of the braking action described above.
In particular, document US2014/0251736A1 shows a caliper of the floating type in which a set of springs of different type and shape cooperate to fix the outer braking element, or outer pad, to the central upper portion of the brake caliper.
However advantageous, such solutions do not fully solve the problem because the braking element of the outer side of the brake body, the side free from supporting bracket, is constrained in weak manner to the caliper body itself, thus being able to turn on itself and/or be arranged differently according to the degree of wear, thus thwarting at least in part the accurate design of the geometric misalignment of the opposite, facing braking elements, made to compensate for the structural deformation of the brake caliper.
Other solutions are known from documents US 2014/367208, DE 10 2011 118736, DE 43 18 744 and U.S. Pat. No. 4,082,166.